Drive Pinion Flange/Yoke and/or Oil Seal Replacement All Except 9.75 Inch Axle
                    
Tools Required
| • | J 22388  Pinion Oil
Seal Installer - Rear (8.6 inch, 9.5 inch axle) | 
| • | J 44414  Pinion Seal
Installer (10.5 inch axle) | 
Removal Procedure
Important: Observe and mark the positions of all the
driveline components, relative to the propeller shaft and the axles, prior to disassembly.
These components include the propeller shafts, drive axles, pinion flanges, output
shafts, etc. Reassemble all the components in the exact places in which you removed
the parts. Follow any specifications, torque values, and any measurements made prior
to disassembly.
- Raise the vehicle. Refer to 
Lifting and Jacking the Vehicle 
 in General Information.
- Remove the tire and wheel assemblies (8.6 inch, 9.5 inch
axles). Refer to 
Tire and Wheel Removal and Installation 
 in Tires and Wheels.
- Remove the rear brake calipers (8.6 inch, 9.5 inch axles).
Refer to 
Rear Brake Caliper Replacement 
 in Disc Brakes.
- Remove the brake rotors (8.6 inch, 9.5 inch axles). Refer
to 
Rear Brake Rotor Replacement 
 in Disc
Brakes.
- Remove the axle shafts (10.5 inch axle). Refer to 
Rear Axle Shaft and/or Gasket Replacement 
 .
 
- Reference mark the rear propeller shaft
(3) to the rear axle pinion yoke (4).
- Disconnect the propeller shaft from the axle.
Wrap the bearing
caps with tape in order to prevent the loss of bearing rollers.
Support the propeller shaft as necessary.
 
- Measure the amount of torque required to
rotate the pinion. Use an inch-pound torque wrench. Record this measurement for reassembly.
This will give the combined preload for the following components:
| • | The pinion pilot bearing (10.5 inch axle) | 
| • | The differential case bearings | 
| • | The axle bearings (8.6 inch, 9.5 inch axles) | 
| • | The axle seals (8.6 inch, 9.5 inch axles) | 
- Draw 2 arrows pointing at each other, one on the pinion stem, the other
on the pinion yoke.
- Record the number of exposed threads on the pinion stem for reference.
 
- Install the J 8614-01 
 as shown.
- Remove the pinion nut while holding the J 8614-01 
 .
- Remove the washer.
 
- Install the J 8614-2 (2) and
the J 8614-3 (3) into the J 8614-01 
 (1) as shown.
- Remove the pinion yoke by turning the J 8614-3 (3)
clockwise while holding the J 8614-01 
 (1).
Use a container in order to retrieve the lubricant. 
- Remove the pinion oil seal. Use a suitable seal removal tool. Do not damage
the housing.
Installation Procedure
 
- Install a new pinion oil seal using theJ 22388 
 or the J 44414 
 .
- Apply sealant, GM P/N 12346004 (Canadian P/N 10953480)
or equivalent, to the splines of the pinion yoke.
- Install the pinion yoke.
Align the marks made during removal.
Notice: Refer to Pinion Flange/Yoke Installation Notice in the Preface section.
- Seat the pinion yoke onto the pinion shaft by tapping it with a soft-faced hammer
until a few pinion shaft threads show through the yoke.
- Install the washer and a new pinion nut.
 
- Install the J 8614-01 
 onto the pinion yoke as shown.
Notice: Use the correct fastener in the correct location. Replacement fasteners
must be the correct part number for that application. Fasteners requiring
replacement or fasteners requiring the use of thread locking compound or sealant
are identified in the service procedure. Do not use paints, lubricants, or
corrosion inhibitors on fasteners or fastener joint surfaces unless specified.
These coatings affect fastener torque and joint clamping force and may damage
the fastener. Use the correct tightening sequence and specifications when
installing fasteners in order to avoid damage to parts and systems.
Important: If the rotating torque is exceeded, the pinion
will have to be removed and a new collapsible spacer installed.
- Tighten the pinion nut while holding the J 8614-01 
 .
Tighten
Tighten the nut until the pinion end play is just
taken up. Rotate the pinion while tightening the nut to seat the bearings.
 
- Measure the rotating torque of the pinion.
Compare this measurement with the rotating torque recorded during removal.
Tighten
Tighten the nut in small increments, as needed,
until the rotating torque is 0.40-0.57 N·m (3- 5 lb in)
greater than the rotating torque recorded during removal.
- Once the specified torque is obtained, rotate the pinion several times
to ensure the bearings have seated. Recheck the rotating torque and adjust if necessary.
 
- Install the propeller shaft (3) to the pinion
yoke (4).
Align the reference marks made during removal.
- Install the propeller shaft yoke retaining clamps and the bolts.
Tighten
Tighten the propeller shaft yoke retaining clamp
bolts to 25 N·m (18 lb ft).
- Install the axle shafts (10.5 inch axle). Refer to 
Rear Axle Shaft and/or Gasket Replacement 
 .
- Install the brake rotors (8.6 inch, 9.5 inch axles). Refer
to 
Rear Brake Rotor Replacement 
 in Disc
Brakes.
- Install the brake calipers (8.6 inch, 9.5 inch axles). Refer
to 
Rear Brake Caliper Replacement 
 in Disc
Brakes.
- Install the tire and the wheel. Refer to 
Tire and Wheel Removal and Installation 
 in Tires and Wheels.
- Inspect and add axle lubricant to the axle housing, if necessary. Refer
to 
Rear Axle Lubricant Level Inspection 
.
- Lower the vehicle.
Drive Pinion Flange/Yoke and/or Oil Seal Replacement 9.75 Inch Axle
                    
Tools Required
| • | J 45710  Pinion Bearing
Oil Seal Installer | 
Removal Procedure
Important: Observe and mark the positions of all the
driveline components, relative to the propeller shaft and the axles, prior to disassembly.
These components include the propeller shafts, drive axles, pinion flanges, 
output shafts, etc. Reassemble all the components in the exact places in which you
removed the parts. Follow any specifications, torque values, and any measurements
made prior to disassembly.
- Raise the vehicle. Refer to 
Lifting and Jacking the Vehicle 
 in General Information.
- Disconnect the propeller shaft from the rear axle pinion yoke. Refer 
to 
Rear Propeller Shaft Replacement 
 in Propeller
Shaft.
 
- Place an alignment mark between the pinion
 and the pinion yoke.
 
- Install the J 8614-01 
 as shown.
- Remove the pinion nut while holding the J 8614-01 
.
 
- Remove the washer.
 
- Install the J 8614-2 (2) and
 the J 8614-3 (3) into the J 8614-01 
 (1) as shown.
- Remove the pinion yoke by turning the J 8614-3 (3) clockwise
 while holding the J 8614-01 
 (1).
Use a container in order to retrieve the lubricant. 
- Remove the pinion oil seal. Use a suitable seal removal tool. Do not 
damage the axle housing.
Installation Procedure
- Apply a light coat of axle lubricant, GM P/N 12378557 
 or equivalent meeting GM Specification 9986207, to the lip of the 
pinion seal.
 
- Install the new seal using the J 45710 
.
 
- Install the pinion yoke.
Notice: Refer to Pinion Flange/Yoke Installation Notice in the Preface section.
- Seat the pinion yoke onto the pinion shaft by tapping it with a soft-faced 
 hammer until a few pinion shaft threads show through the yoke.
 
- Install the washer.
 
- Install the new pinion nut
 
- Install the J 8614-01 
 onto the pinion yoke as shown.
Notice: Refer to Fastener Notice in the Preface section.
- Tighten the pinion nut while holding the J 8614-01 
.
Tighten
Tighten the pinion nut to 370 N·m (273 lb ft).
- Install the propeller shaft to the rear axle pinion yoke. Refer to 
Rear Propeller Shaft Replacement 
 in Propeller Shaft.
- Inspect and add axle lubricant to the axle housing, if necessary. Refer
to 
Rear Axle Lubricant Level Inspection 
.
- Lower the vehicle.